mic4574 Micrel Semiconductor, mic4574 Datasheet - Page 4

• Manufacturer Part Number: mic4574
• Description: Mic4574 200khz Simple 0.5a Buck Regulator
• Manufacturer: Micrel Semiconductor

MIC4574
Block Diagrams
M9999-062105
Shutdown
Enable
Shutdown
Enable
SHDN
SHDN
MIC4574
MIC4574-x.x
Regulator
Regulator
Oscillator
Oscillator
Internal
200kHz
200kHz
Internal
Block Diagram with External Components
Block Diagram with External Components
[Adjustable]
parator
parator
Com-
Adjustable Step-Down Regulator
Com-
Error
Amp.
Error
Amp.
Fixed Step-Down Regulator
Shutdown
Shutdown
Thermal
Thermal
Bandgap
Bandgap
1.23V
1.23V
Driver
Driver
Current
Current
Limit
Limit
4
GND
R2
GND
R1
0.5A
Switch
0.5A
Switch
+24V max.
+24V max.
V
V
IN
IN
SW
FB
SW
FB
V
R1
D1
D1
C
OUT
C
IN
IN
L1
L1
R2
V
R1
R2
REF
V
V
OUT
REF
R2
R1
+ 1
1
C
C
OUT
OUT
V
V
OUT
OUT
Micrel, Inc.
June 2005